Kinetic Study of the Electric Field-Induced Cholestericnematic Transition in Liquid Crystal Films: 1. Relaxation to the Cholesteric State
Relaxation of cholesteric liquid crystals from the electric-field-induced nematic state back to the cholesteric state was studied by measuring the transmission of polarized light through the sample. Variables included time, temperature, wavelength and bias. The relaxation transient was found to include optical rotation which corresponded to the optical sense of the material. The rotatory dispersion furthermore was correctly specified by deVries’ formula. The results point out the significance of the basic cholesteric parameters of pitch and sense. An attempt is made to relate the relaxation phenomena to the molecular system.
KeywordsLiquid Crystal Polar Angle Polar Plot Cholesteric Liquid Crystal Threshold Field
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